Electric lamp



May 7, 1946. J. GOLOB ET AL ELECTRI C LAMP Original Filed Aug. 5, 1942 INVENTORJT 'QCA/SEM l 477' RNA-)s Patented May 7, 1946 ELECTRIC LAMP John E. Golob and Arnold D. Dircksen, Dayton, Ohio Original application August 5, 1942, Serial No.

453,732. Divided and this application February 28, 1945, Serial No. 580,242

4 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to a battery-operated electric lamp, and more particularly to the construction of the lamp casing.

This is a division of our U. S. application for Letters Patent for Identification light for aerial delivery containers, Serial No. 453,732, filed August 5, 1942, which matured into Patent No. 2,376,330, issued May 22, 1945.

An object of our invention is to provide an improved method for constructing an electric lamp having a battery casing formed of molded plastic material with an incandescent lamp mounted on each end of the casing. In a lamp of this nature it is necessary to have one or more wires extending from one end of the lamp to the other in order to complete the electricalcircuitbetween the two incandescent lamps. In

order that this end-to-endwiring may be completely enclosed and protected from injury, and also for the purpose of facilitating the Wiring of the electric circuits of the lamp, we have devised what we believe to be a new and novel method of lamp construction wherein the cylindrical casing is formed in two halves with channels or recesses molded in the longitudinal edges of one of the halves for receiving the end-to-end wiring. 'Ihe wiring is placed in the recesses and the electrical circuits are completed, after which the halves are secured together, preferably being cemented together, to form the completed casing.

A further object of our invention is to provide a novel plastic lamp case, formed of a pair of tubular and preferably semi-cylindrical members, one of which is provided with a recess extending longitudinally along one or both of its edges so as to form a wire-enclosing and protecting passageway through the wall of the case when the members are placed and secured together to form a cylindrical lamp casing. Hence, the electrical wiring of the lamp circuit will be completely enclosed within the Wall of the casing and will thus be protected against injury which might occur if the wiring were left exposed.

With these and other objects in view, which will become more apparent as the description proceeds, we will now describe our invention fully, it being understood that the specic embodiment of our invention which is disclosed may be varied in its various details without departing from the spirit or scope of the appended claims.

In the drawing:

Fig. 1 is partly a longitudinal central section and partly a side view of the lamp embodying this invention. V

Fig. 2 is an enlarged cross-sectional view thereof, taken on line 2 -2 of Fig. 1.

As disclosed in thedrawing, our novel electric lamp 20 is comprised of a lamp casing which consists of a pair of semi-tubular members 26 and 28, which are preferably semi-cylindrical and are secured together to form a cylindrical lamp casing. These members are preferably constructed of a molded plastic material and are cemented together with a suitable plastic cement to form the completed lamp casing. On each end of the casing is provided a reduced portion on which threads 30 are molded.

The transparent plastic lenses 32 utilized herein are provided with internal threads so as to enable them to be screwed on the threads 30 on each end of the casing. Projections 34 are preferably formed around the perimeter of each lens 32 so as to facilitate attaching and removing the lenses on the ends of said casing.

An end cap 42 is permanently secured in the left-hand end of the lamp casing and an end cap 44 is removably attached to the right-hand end of the casing. Both caps are constructed of plastic or other Velectrical insulating material and serve as a means for supporting the lamp receptacles provided at each end of the casing.

A lamp receptacle 45 is secured to the cap 42 at the left-hand end of the casing by means of rivets 48 and 5D. The rivet 48 is electrically connected to the center contact of the receptacle, while the rivet 50 is electrically connected to the threaded portion of the receptacle. The rivet 48 is electrically connected with another rivet 54 located at the right-hand end of the casing by means of a wire 5 2 passing through a recess provided within the wall of the container. The rivet 54 serves to secure the contact strip 56 to the outer surface' of the casing and is electrically connected to this strip. The rivet 50 is electrically connected with another rivet 6) located at the right-hand end of the casing by means of a wire 58 which passes through a second channel located within the wall of the casing. The rivet 60 makes electrical contact with the strip 62 and serves to secure this strip to the outside of the casing.

A lamp receptacle (not shown) is secured to the removable end cap 44 by means of rivets B6 and 68 at the right-hand end of the casing, in th'e same manner as the receptacle 4S at the lefthand end of the casing. The rivet 66 is electrically connected with a pin 1U projecting laterally from one side of cap 44 and is also connected With the threaded portion of the receptacle, the same as rivet 50 at the left-hand end. The rivet 68 is electrically connected with a pin 12 projecting laterally from the opposite side of the cap 44 and is also connected with the center contact of the receptacle, the same as rivet 48 at the left-hand end.

The right-hand end of the contact strip 56 is provided with a well-known bayonet slot which cooperates with said pin 'l0 for the purpose of holding the cap securely in place in the end of the casing and also for making electrical contact between the pin and other portions of the wiring circuit. A similar bayonet slot is provided in the metallic strip 62, this second slot cooperating with the pin 'I2 for a similar purpose.

A helical spring 74 is located ln the righ t-hand end of the casing, one end of this spring bearing against the negative terminal of an electrical cell I6 located Within the casing, and the other end bearing against a metal plate which is electrically connected with the rivet 68. Another electrical cell 18 at the left-hand end of the lamp casing has its positive terminal pressed against the metallic strip 19 by action of the spring 74. Said strip 19 is electrically connected to a rivet 82 located in the right-hand end of the casing by means of a wire 89 passing through the upper channel in the lamp casing. This rivet serves to hold a contact strip 84 in position on the outside of the casing as well as to make electrical contact with the strip.

The interponent 85 of non-conductive material is normally positioned between the contacts 56 and 84, as illustrated in Fig. 1 of the drawing, so as to interrupt the electrical circuit of the lamp, and is removed by pulling the operating cord 86 attached to member 85, whereupon the circuit to both of the lamps will be established and they will be lighted, as more fully disclosed and claimed in the above-identied parent case.

As was mentioned earlier in this description the lamp casing is provided with channels or recesses extending lengthwise through the wall thereof for the purpose of accommodating the wires 52, 58 and 80. The production of these channels is facilitated by making the lamp casing in two halves 26 and 28. The half 28 is provided with longitudinally extending recesses S4 molded in both of its edges and also with longitudinal tongues 98 molded along the inner edges of the recesses. The half 26 is provided with grooves to receive th'e tongues 98 and, as will be seen from Fig. 2, when the two halves are placed together they will form a completed lamp casing having tightly sealed channels S4 which extend lengthwise through the wall of the casing. The wires of the lighting circuit are inserted in these channels and the wiring circuits completed before the halves are placed together and cemented. This greatly simplies the wiring of the lamp and, at the same time, affords a completely enclosed conduit for the wires where they will be well protected from injury.

We claim:

l. An electric lamp case of molded plastic construction comprising a pair of semi-cylindrical members at leastI one of which is provided with' a longitudinally extending recess molded in at least one of which is provided with a longitudinally ex` tending recess molded in at least one of its longitudinal edges, said recess extending along substantially the entire length of said edge so as to provide a wire-accommodating recess within the wall of said case, and cooperating means provided on the joining edges of said members alongside of said recess to provide a completely inclosed recess when said members are placed together to form a cylindrical lamp casing.

2. An electric lamp case of molded plastic construction comprising a pair of semi-cylindrical members at least one of which is provided with a longitudinally extending recess molded in at least one of its longitudinal edges, said recess extending along substantially the entire length of said edge, said member being also provided with a longitudinally extending tongue molded along one edge of said recess, and a longitudinally extending groove molded in the edge of the other of said members for receiving said tongue so as to provide a completely enclosed wire-accommodating recess within the wall of said case when said members are placed together to form a cylindrical lamp casing.

3. An electric lamp case of molded plastic construction comprising a pair of semi-tubular members at least one of which is provided with a longitudinally extending recess molded in at least one of its longitudinal edges, said recess extending substantially the entire length of said edge, circuit wires extending through' said recess from one end of the lamp to the other, a longitudinally extending tongue provided along said one edge 7 tongue to provide a completely enclosed recess within the wall of said case which contains said wires when said pairs of members are secured together forming a tubular lamp casing.

4. An electric lamp case of molded plastic construction comprising a pair of semi-cylindrical members, one of said members being provided with a pair of tongues and a pair of recesses inwardly of the tongues, one tongue and one recess extending longitudinally along each' of the two opposite edges of said member, a groove extending longitudinally in each of the two opposite edges of the other of said members to receive Said tongues, and circuit wires mounted in said recesses and extending from one end to the other of said members, said members being cemented together to form a cylindrical lamp casing and completely enclosing the circuit wires in said recesses.

JOHN E. GOLOB. ARNOLD D. DIRCKSEN. 

